Hemispheric disconnection as a basis for neurodegeneration in apraxia and Alzheimer’s disease
摘要
Apraxias, traditionally viewed as executive disorders secondary to focal lesions, are here reformulated as systemic outcomes of progressive interhemispheric disconnection—particularly relevant in the early stages of Alzheimer’s disease.
ObjectiveTo propose an integrated theoretical model that redefines apraxias from a neurosemiotic and embodied perspective, linking them to corpus callosum degeneration and the breakdown of sensorimotor gesture networks.
MethodsThis contribution is based on a transdisciplinary conceptual review, integrating data from neuroscience, body semiotics, phenomenology, and recent clinical studies. The reflection is supported by a synthesis of neuroanatomical, cognitive, and behavioral findings regarding proprioceptive function and hemispheric lateralization.
Main resultsFour forms of apraxia (simple, ideational, ideomotor, and constructive) are distinguished as differential configurations of embodied gesture disintegration. The proposed model links these manifestations to the loss of integration among gesture syntax, proprioceptive semantics, and contextual pragmatics, opening new hypotheses for the early diagnosis of Alzheimer’s disease.
ConclusionsApraxias may be reinterpreted as predictive indicators of early cognitive decline, providing a foundation for the development of more sensitive diagnostic tools and rehabilitation strategies centered on gesture narrative, body memory, and embodied identity.